1. Field of the Invention
The present invention relates to an improvement in an outboard motor auxiliary fuel tank/fuel pump assembly that includes an auxiliary fuel tank that is disposed in a space on either of the front, back, left and right sides of an engine in an engine compartment of an outboard motor and stores fuel that is fed from a fuel tank.
2. Related Art
A conventional outboard motor auxiliary fuel tank/fuel pump assembly is already known and disclosed in, for example, Japanese Patent Application Laid-open No. 10-184375.
When installing such a conventional auxiliary fuel tank/fuel pump assembly in a relatively small engine compartment, a space located either to the front or rear of the engine or the left or right side of the engine is utilized to position the assembly depending on the type of engine. It is well known in the industry that even in a state where the outboard motor is tilted up, for example, when traveling in shallow water, it is necessary for the pivot shaft of the float valve of the auxiliary fuel tank to always be parallel relative to the tilt shaft of the outboard motor in order to secure normal operation of the float valve. Therefore, when the auxiliary fuel tank/fuel pump assembly is installed in any of the above-mentioned front, rear, left, and right spaces, the orientation of the auxiliary fuel tank is determined by the orientation of the pivot shaft of the float valve.
Accordingly, it has been general practice in the industry to establish the spaces to the front and rear of the engine in the engine compartment so as to be narrower in the front-and-rear direction than in the left-and-right direction, and the spaces on the left and right sides of the engine are set so as to be narrower in the left-and-right direction than the front-and-rear direction in order to avoid restricting the maximum steering angle caused by the raised position of the rear end of the outboard motor when it is tilted up or by the positions to which opposite sides of the outboard motor protrude when steering to the left or right. It is therefore necessary for the auxiliary fuel tank and the fuel pump to be connected so as to be aligned in the left-and-right direction when the auxiliary fuel tank/fuel pump assembly is arranged in the space to the front or rear of the engine. Furthermore, it is necessary for the auxiliary fuel tank and the fuel pump to be connected so as to be aligned in the front-and-rear direction when the assembly is arranged in the space on the left or right side of the engine. Because of this difference in the position of the auxiliary fuel tank to which the fuel pump is connected, a different conventional auxiliary fuel tank is used exclusively for each of the above-described cases and is produced so as to correspond to the space where the auxiliary fuel tank/fuel pump assembly is installed. This decreases the effectiveness of mass-producing the auxiliary fuel tank, which results in increasing manufacturing costs.
It is an object of the present invention to at least overcome the above-described drawbacks of the conventional fuel tank/fuel pump assemblies.
It is also an object of the present invention to provide an outboard motor auxiliary fuel tank/fuel pump assembly that can reasonably be arranged within any of the spaces to the front, rear, left, and right sides of the engine even when the same type of auxiliary fuel tank is used. The structural arrangement of the present invention increases the effectiveness of mass-producing the auxiliary fuel tank, improves space efficiency, and decreases manufacturing costs.
According to a preferred embodiment of the present invention, there is provided an outboard motor auxiliary fuel tank/fuel pump assembly that includes an auxiliary fuel tank disposed in an engine compartment of an outboard motor that stores fuel fed from a fuel tank on a hull side. A fuel pump is joined to one side of the auxiliary fuel tank and supplies the fuel stored within the auxiliary fuel tank to a fuel injection valve of an engine. A float valve having a float is provided within the auxiliary fuel tank and opens/closes a fuel inlet port of the auxiliary fuel tank according to the level of the stored fuel. The float is supported in a vertically swingable manner in the auxiliary fuel tank via a pivot shaft that is parallel to a tilt shaft of the outboard motor. An air vent pipe is connected to the auxiliary fuel tank and communicates with an upper space within the auxiliary fuel tank. The assembly also includes first and second mounting parts on which the fuel pump is mounted. The first and second mounting parts are formed, respectively, on an outer face of the auxiliary fuel tank that is vertical and perpendicular to the tilt shaft and on an outer face of the auxiliary fuel tank that is vertical and parallel to the tilt shaft.
In accordance with the preferred embodiment, the same type of auxiliary fuel tank can be used where the auxiliary fuel tank/fuel pump assembly is arranged in the space to the front or rear of the engine by connecting the auxiliary fuel tank and the fuel pump so as to be aligned in the left-and-right direction, and where the auxiliary fuel tank/fuel pump assembly is arranged in the space on the left or right side of the engine by connecting the auxiliary fuel tank and the fuel pump so as to be aligned in the front-and-rear direction. It is therefore possible to reasonably provide a structural arrangement of the auxiliary fuel tank/fuel pump assembly using the same type of auxiliary fuel tank in all cases, thereby enhancing the space efficiency and mass-production of the auxiliary fuel tank. Moreover, in all cases, since the pivot shaft of the float valve within the auxiliary fuel tank is maintained parallel to the tilt shaft, the float valve can properly be operated when the outboard motor is tilted up.
In accordance with a second embodiment of the present invention, there is an outboard motor auxiliary fuel tank/fuel pump assembly that further includes first and second connecting bosses provided, respectively, on the outer face of the auxiliary fuel tank on which the first mounting part has been formed and on the outer face of the auxiliary fuel tank on which the second mounting part has been formed. A suction pipe of the fuel pump is connected to the first and second connecting bosses. The connecting bosses include a blocking wall through which a hole is made when the suction pipe is connected thereto.
accordance with the second embodiment, when the fuel pump is mounted either on the first or second mounting part of the auxiliary fuel tank, the suction pipe is connected to the corresponding connecting boss at the same time, such that the connection operation is performed rather rapidly.
The first and second mounting parts may correspond to first and second bosses, and the fuel pump may correspond to a secondary fuel pump.